Vitamin D Improves Muscle Function

April 8, 2013. The March, 2013 issue of The Journal of Clinical Endocrinology & Metabolism reports the finding of researchers at Newcastle University in England of a positive effect for vitamin D supplementation on the muscle function of deficient adults.

Dr, Akash Sinha and colleagues used magnetic resonance spectroscopy in a lower leg muscle of twelve participants before and after twelve weeks of vitamin D supplementation to evaluate phosphocreatine recovery kinetics as an assessment of mitochondrial oxidative phosphorylation. Phosphocreatine is used by the cells’ mitochondria to manufacture adenosine triphosphate (ATP)--a molecule needed by muscle for movement. Rapid replenishment of phosphocreatine by the mitochondria following muscle contraction is an indicator of improved mitochondrial efficiency.

The team observed a reduction in phosphocreatine recovery half-time after treatment with vitamin D, which indicates an improvement in maximal oxidative phosphorylation. "The scans provided a unique window into what is really going on in the muscle as it works,” Dr Sinha explained. “Examining this small group of patients with vitamin D deficiency who experienced symptoms of muscle fatigue, we found that those with very low vitamin D levels improved their muscle efficiency significantly when their vitamin D levels were improved."

"We have proved for the first time a link between vitamin D and mitochondria function,” Dr Sinha announced. "Of the patients I see, around 60% are vitamin D deficient and most people living north of Manchester will struggle to process enough vitamin D from sunlight alone, particularly during winter and spring. So a simple vitamin D tablet could help boost your energy levels – from within the cells."